XEROPLANTS - plants that live adapted to very dry environment. Adaptations:
1) Stomata - many have fewer which are sunken decreasing exposure to air currents so less H2O is lost by transpiration. Some xerophytes only open their stomata at night when its dark and cooler to limit H2O loss by transpiration
2) Leaves - some have small leaves to reduce the surface area which will reduce H2O loss by transpiration. Others have vertically orientated leaves to decrease the surface area exposure to light and heat and decrease H2O lost. Other have roled leaves to prevent H2O loss and maintain humid air around the stomata. This prevents exposure to air current and reduces the water potential gradient. They also reduce surface area of the leaf that is exposed to heat, light and waind which will reduce transpiration further.
3) Cuticle - many xerophytes have thick waxy cuticles again to prevent H2O loss
4) Stem - some have hairs convering stem. They help shade and cool the plant leading to a reduced rate of transpiration. They also trap a layer of moist air which decreases exposure to air currents and reduces the concentration gradient of water and air between the plant and the atmopshere. So plant loses less H2O
5) Roots - xerophytes have a large and widespread root system system so they can take in as much H2O as possible. The cortex of their roots there is a shorter distance between H2O in the soil and the xylem. So H2O can be taken up quicker
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